#pragma once 

/////////////////////////
//二叉树类型定义

template<typename E>
struct BiTNode
{
    E data;
    BiTNode *lchild,*rchild;
};

template<typename E>
using BiTree = BiTNode<E> *;

////////////////////////////
//二叉树基本操作

//先序遍历二叉树Preorder（T,visit）
template <typename E, typename F>
void Preorder(BiTree<E> T,F visit)
{
    if(T){
        visit(T->data);
        Preorder(T->lchild,visit);
        Preorder(T->rchild,visit);
    }
}

///中序遍历二叉树 Inorder(T,visit)
template <typename E, typename F>
void Inorder(BiTree<E> T,F visit)
{
     if(T){
        Inorder(T->lchild,visit);
         visit(T->data);
        Inorder(T->rchild,visit);
    }
}

//后序遍历二叉树 Postorder(T,visit)
template <typename E, typename F>
void Postorder(BiTree<E> T,F visit)
{
     if(T){
        Postorder(T->lchild,visit);
        Postorder(T->rchild,visit);
        visit(T->data);
    }
}
///求二叉树节点 NodeCount(T)
template <typename E>
int NodeCount(BiTree<E> T)
{
    if (T == nullptr)
            return 0;
        auto L = NodeCount(T->lchild);
        auto R = NodeCount(T->rchild);
        return L + R + 1;
}
///求二叉树叶子节点数LeafCount(T)
template <typename E>
int LeafCount(BiTree<E> T)
{
    if(T == nullptr)
        return 0;
    if(T->lchild == nullptr && !T->rchild )
        return 1;
    else{
        auto L = LeafCount(T->lchild);
        auto R = LeafCount(T->rchild);
        return L + R;
    }
}
///求二叉树的深度 Depth(T)
template <typename E>
int Depth(BiTree<E> T)
{
    if(T == nullptr)
        return 0;
    auto L = Depth(T->lchild);
    auto R = Depth(T->rchild);

    return L > R ? L + 1 : R + 1;
}

#include <iostream>
using std::cout;
using std::endl;

///打印二叉树
template <typename E>
void Print(BiTree<E> T, char prefix = '$',int level = 0)
{
    if(T){
        Print(T->rchild,'/', level + 1);
        for(int i = 0; i < level; ++i) cout << "  ";
        cout << prefix << ' ' << T->data <<endl;
        Print(T->lchild,'\\',level + 1);
    }
}

#include <iostream>
using std::cin;
using std::noskipws;
///建立二叉树CreatBinaryTree()
BiTree<char> CreateBinaryTree()
{
    char c;
    cin >> noskipws >> c;
    if (c == ' ') return nullptr;
    auto T = new BiTNode<char>{c,nullptr,nullptr};
    T->lchild = CreateBinaryTree();
    T->rchild = CreateBinaryTree();
    
    return T;
}

///销毁二叉树Destro(&T)
template <typename E>
void Destroy(BiTree<E> &T)
{
    if(T){
        Destroy(T->lchild);
        Destroy(T->rchild);
        delete T;
        T = nullptr; 
    }
}
////////////////////////////
//二叉排序树基本操作

//// 二叉排序树基本操作算法 SearchBST(T,e)
template <typename E>
BiTree<E> SearchBST(BiTree<E> T,E e)
{
    if(!T || T->data == e)
        return ;
    else if (e < T -> data)
        return SearchBST(T->lchild,e);
    else  
        return SearchBST(T->rchild,e);
} 

/// 二叉排序树找最小 FindMinBST(T)
template <typename E>
BiTree<E> FindMinBST(BiTree<E> T)
{
    if(T)
        while (T->lchild)
            T = T->lchild;
        return T;
}

///二叉排序树找最大 FindMaxBST（T）
template <typename E>
BiTree <E> FindMaxBST(BiTree<E> T)
{
    if (T)
        while (T->rchild)
            T = T ->rchild;
    return T;
}

///二叉排序树插入 InsertBST(&T,e)
template <typename E>
void InsertBST(BiTree<E> &T,E e)
{
    if (T == nullptr)
        T = new BiTNode<E>{e,nullptr,nullptr};
    else if (e < T ->data)
        InsertBST(T ->lchild,e);
    else if(e > T->data)
        InsertBST(T->rchild,e);
    else
        ;
}

/// 二叉排序树删除 DeleteBST(&T,e)
template<typename E>
void DeleteBST(BiTree<E> &T, E e)
{
    if (T == nullptr) return;
    else if (e < T-> data )
        DeleteBST(T->lchild,e);
    else if (e > T->data)
        DeleteBST(T ->rchild,e);
    else  { // T->data == e
        if(T->lchild && T ->rchild){// T 有连个子树
            T->data = FindMaxBST(T->lchild) ->data;
            DeleteBST(T->lchild,T->data);
        }else{
            auto oldNode = T;
            T = T->lchild ? T->lchild : T->rchild;
            delete oldNode;
        }

    }
}
